Abstract: The formation in a liquid hydrocarbon fuel of ice particles having a weight average particle size greater than 1 ?m when said liquid hydrocarbon fuel is cooled to temperatures in the range of from 0 to ?50° C. can be reduced or eliminated by use of at least one surfactant that is capable of dispersing water in said liquid hydrocarbon fuel to provide a stable clear water-in-oil microemulsion wherein the droplet size of the dispersed water phase is no greater than 0.25 ?m.

Abstract: A composition comprising a mixture of emulsifying agents including a polyisobutylenesuccinimide and a sorbitan ester in a weight ratio of from about 1:8 to about 1:1 may be used in a water-in-oil microemulsion to improve low and/or high temperature stability of the microemulsion.

Abstract: In one aspect, the present invention provides a water-in-oil emulsion comprising from about 5 to about 40 wt % aqueous phase and from about 95 to about 60 wt % non-aqueous phase, said aqueous phase being dispersed in said non-aqueous phase in the form of droplets having an average droplet size no greater than about 0.1 ?m, said emulsion comprising: at least 60 wt % of an oil selected from fuel oils, lubricating oils and mixtures thereof, from about 1 to about 30 wt % of emulsifying agents, and the balance to 100 wt % water, wherein said emulsifying agents include a fatty (C8-C24)-amido-(C1-C6)alkyl betaine, is useful as a fuel, coolant or lubricant.